Kekkai
A kekkai (barrier) is a kekkaishi's main source of offense and defense, and they have a wide variety of uses, in and out of combat. Offensive Kekkai 'Capture & Collapse: The Basics' Among the most basic uses of a kekkai are the capture and destruction of ayakashi. It should be noted, however, that an ayakashi that can be immediately be detained and destroyed, with no damage beforehand, is generally thought to be either fairly weak, or simply outclassed by the kekkaishi's skill. Some ayakashi have special abilities that allow them to either avoid or escape from kekkai. Stronger ayakashi must be weakened considerably to improve the kekkai's effectiveness. The strength of a kekkai depends most on the kekkaishi's skill and feelings, rather than their power, although it is repeatedly shown that kekkaishi with great power can make kekkai of enormous size when needed, while others cannot. In terms of offense, the most commonly seen attack involving kekkai is the destruction of a portion of an enemy by collapsing a kekkai around it. While this is an excellent method to weaken ayakashi, a great deal of them are able to regenerate quickly, and the rate at which they heal is always accelerated while in Karasumori. Repeated destruction of parts tends to gradually tire all but the strongest ayakashi, so this is still an acceptable method with many of them. 'Spear/Arrow/Hammer' A technique popularized by Tokine is the kekkai spear or arrow: a rectangular, rapidly extending kekkai that pierces the opponent's body. With larger foes, she tends to use multiple spears at once to great effect.Kekkaishi anime, Episode 20 She has also been known to use a far weaker (but still rather painful), blunted version on Yoshimori and Gen Shishio as punishment for small offenses. Yoshimori occasionally uses this as well, but tends to add far more power, resulting in a larger, harder-hitting impact.Kekkaishi anime, Episode 29 'Multi-Layer' Using one or more kekkai within another kekkai is very effective. Not only does this make it harder and more time-consuming for the enemy to escape, it also increases the strength of the eventual collapse, and is useful against ayakashi with tough outer shells.Kekkaishi anime, Episode 13 Defensive Kekkai The most common defensive use of kekkai is surrounding a target (either the enemy or the kekkaishi them self) to prevent attack. Kekkai can also be manipulated so that they only target certain things: Yoshimori has perfected a "naptime kekkai" that only prevents his grandfather from entering while Yoshimori is asleep, but allows others to pass through freely. 'Rubber/Bouncy' While most kekkai are quite solid, kekkaishi occasionally produce kekkai that have a built-in amount of give. These are used to reflect or bounce back certain attacks, or to cushion the fall of allies.Kekkaishi anime Episode 18 'Wall' Aside from the usual cube shape, kekkai can be shaped into long walls to block access.Kekkaishi anime, Episode 6 'Elevator' A slower, horizontal version of the kekkai arrow that lifts a target into the air. Kekkaishi also use this to raise themselves above battlefields, sometimes with an additional, outer elevator surrounding them to prevent attack. 'Stairs/Floating' Kekkai placed or produced in mid-air provide useful platforms for standing or traveling high above the ground. Yoshimori and Tokine created a relay system of these, allowing Gen (and later Souji) to bounce rapidly between them, landing swift strikes on enemies.Kekkaishi anime, Episode 14 References